Puritan Board Junior
Actually, I believe it can be so proved -- though it is not necessary for the OP that I prove it. Rather, the burden is upon you. So I'll give you what I regard as proof of it, but the real onus is on you to demonstrate that my exegesis is incorrect and not even plausible.No former "song" appointed to be sung in corporate worship can be proved to exist. On the basis that there is no other song appointed for use in "public worship," the limiting function of the regulative principle indicates exclusive psalmody.
2 Chr 29:28 says:
Then in v. 30, which begins with a narrative preterit (best translated, "then" or "next" -- but "moreover" is okay), it says:And all the congregation worshipped, and the singers sang, and the trumpeters sounded: and all this continued until the burnt offering was finished.
The point is, even under the reformer's watch, there was signing that was not the Psalms, and after that, Hezekiah had the Psalms sung. V. 30 would not make sense if v. 28's singing were Psalms.Moreover Hezekiah the king and the princes commanded the Levites to sing praise unto the Lord with the words of David, and of Asaph the seer. And they sang praises with gladness, and they bowed their heads and worshipped.
But it is not silent, as I have just demonstrated.2 Sam. 23 indicates the "inspired" nature of the songs we know were appointed for public worship; we do not know of any other songs appointed for public worship; hence all the songs appointed for public worship were "inspired." The "exclusivity" of the argument comes from the fact that Scripture is silent as to the use of any other compositions.
While it does not say what the song was, it quite clearly could not have been the Psalms, or v. 30 would make no sense.